I. Field of the Invention
The present invention relates generally to tampon assemblies. More particularly, the present invention relates to a supporting rim structure of an open insertion end tampon applicator that provides for an improved method for forming a rounded insertion end of a tampon pledget assembled therein.
A tampon assembly, including a tampon pledget and a tampon applicator, may have a rounded insertion end to facilitate the insertion of the tampon pledget into a vagina. The rounded insertion end may be formed on the applicator, such as a petal tip applicator, or a pledget that is positioned in the applicator, such as an open insertion end applicator.
For a petal tip applicator, curved flexible petals at the insertion end of the applicator enclose and cover a pledget within the applicator. Alternatively, for an open insertion end applicator, a pledget having a rounded insertion end extends from a blunt open end of the applicator. Since the exposed edge of a blunt, open end applicator may be uncomfortable to a user, a pledget having a rounded insertion end is positioned in front of the blunt open end to provide better comfort.
For open insertion end applicators, when forming a rounded shape at the insertion end of a pledget, a strong axial force must be applied to the fibers of the pledget to achieve a true rounded, hemispherical shape. Since this axial force tends to exceed the columnar strength of the pledget, the pledget requires both axial and radial support about its outer surface during formation of the rounded insertion end. Existing methods utilize special apparatuses for providing the necessary axial and radial support to the pledget during formation of its rounded insertion end. Since the insertion end is formed before placement of the pledget within the applicator, the pledget must then be carefully inserted and secured in the applicator without damaging the formed insertion end. Such insertion can be very difficult.
II. Description of the Prior Art
Processes for providing support to the outer surface of a tampon pledget as its rounded insertion end is formed are known. For such processes, the rounded insertion end is formed before the pledget is positioned within a tampon applicator. For example, U.S. Pat. No. 2,077,231 to C. A. Fourness, et al., which issued on Apr. 13, 1937; U.S. Pat. No. 2,799,055 to J. A. Carrier, which issued on Jul. 16, 1957; U.S. Pat. No. 3,683,915 to J. A. Voss, which issued on Aug. 15, 1972; and, U.S. Pat. No. 4,685,178 to T. Nakanishi, which issued on Aug. 11, 1987.
Also, placement of a pledget in an applicator so that its insertion end projects beyond the insertion end of the applicator is also known. For example, U.S. Pat. No. 2,355,628 to V. Calhoun, which issued on Aug. 15, 1944; U.S. Pat. No. 2,386,590 to V. Calhoun, which issued on Oct. 9, 1945; U.S. Pat. No. 3,999,549 to R. P. Poncy, et al., which issued on Dec. 28, 1976; and, U.S. Pat. No. 4,077,408 to J. L. Murray, et al., which issued on Mar. 7, 1978. Each provides a pledget having a curved or semi-curved insertion end that is exposed at one end of the applicator.
Further, a special rim that supports a dispensed product, such as a suppository, in an applicator is described in U.S. Pat. No. 3,677,465 to J. A. Voss titled Applicator Tubes For Suppositories and the Like, which issued on Jun. 6, 1972. The patent provides a suppository dispenser having segments at the forward end of a cylindrical applicator that drop into a reduced neck portion of the suppository at right angles. Since the suppository is a substantially rigid item, the segments simply prevent the suppository from slipping out of the applicator and are designed to flare outward when the suppository is ejected from the applicator.
Although U.S. Pat. No. 3,667,465, cited above, suggests that its applicator may be used for tampon pledgets, it requires the formation of a substantially rigid neck portion and a tapered rear face that add to the complexity and cost of manufacturing such a pledget. Also, the patent provides that the back end of the suppository is tapered to facilitate insertion into the applicator from the insertion end, thus avoiding any damage to the insertion end of the suppository. However, the patent presumes that the insertion end is formed before placement within the applicator and does not provide a way to insert the suppository or pledget through the back end, opposite the blunt open end, of an applicator. In addition, this patent does not describe or suggest a method for forming a rounded insertion end of a suppository or pledget.
Short segments formed at the forward end of an applicator are known for tampon pledgets as well as suppositories. For example, U.S. Pat. No. 3,717,149 to B. P. Morane titled Injector Package For Catamenial Tampon, which issued on Feb. 20, 1973, provides short segments or petals at the blunt, open insertion end applicator which petals cover the insertion end of the pledget. Thus, similar to a petal tip applicator, the segments or petals are essentially confined to the forward edge of the pledget and do not provide any support to the pledget in the applicator.
Accordingly, none of the above patents describe or suggest a device or method for forming a rounded insertion end to a tampon pledget after the pledget has been assembled in the open insertion end of the tampon applicator.